Parts

Name Purpose / Function iGEM Part
GAL4 DNA-Binding Domain (GAL4 DBD) Serves as a control DBD in yeast two-hybrid assays; binds GAL4-UAS sequences to initiate transcription when paired with AD fusion. BBa_25MD9GE0
LexA DNA-Binding Domain (LexA DBD) Core DNA-binding region from E. coli LexA repressor; used as bait domain in LexA-based Y2H system to avoid cross-talk with yeast GAL4 system. BBa_K5477045
ESR1 (ERα) Full-Length CDS Encodes human estrogen receptor α; mediates ligand-dependent dimerization upon binding estradiol or BPA. BBa_K2365510
Flexible Peptide Linker Connects functional protein domains (e.g., LexA-DBD and ESR1 LBD) without interfering with folding or activity. BBa_K3712011
LexA Operator Sites (LexAop) DNA recognition sites for LexA DBD; placed upstream of reporter genes (e.g., lacZ) to control transcriptional output. BBa_K5154000
Reporter: lacZ (β-Galactosidase) Reporter enzyme that produces a colorimetric signal (yellow/blue) to indicate successful ESR1 dimerization in yeast. BBa_25ZHGV3T
Reporter/Selection Marker: LEU2 Yeast auxotrophic marker allowing growth in leucine-deficient media; part of the reporter plasmid system. BBa_K5159020
pGilda (LexA-BD Vector) Bait plasmid carrying LexA DNA-binding domain under GAL1 promoter; used for expressing LexA-ESR1 fusion proteins. BBa_25TNIQC1
pB42AD / pJG4-5 (B42 AD Vector) Prey plasmid expressing B42 activation domain fusions; interacts with bait proteins to activate reporter transcription. BBa_25QXAFSB
pGEM-T (TA Cloning Vector) PCR product cloning vector with T-overhangs; used as ESR1 gene source before subcloning into Y2H plasmids. BBa_252BAXQ8
EGY48 Yeast Strain Host yeast strain for LexA-based Y2H; contains chromosomal LexAop-lacZ reporter and auxotrophic markers. BBa_250R8SL4
EcoRI Restriction Site Restriction enzyme site (GAATTC) used for cloning ESR1 fragments into both plasmids. BBa_255XOW4U
BamHI Restriction Site Restriction enzyme site (GGATCC) used for directional cloning in pGilda vector. BBa_252D4G09
ESR1 Mutant FW Primer Forward primer for introducing site-specific mutations into ESR1 LBD (Y519, G523, N524, T529, L535). BBa_2555K2IP
ESR1 Mutant 300 (RV) Primer Reverse primer targeting ESR1 300+ region for amplification and mutation validation. BBa_25QB456Z